Update README.md according to validation split

README.md

@@ -65,8 +65,8 @@ dataset_info:
     num_bytes: 2805711609
     num_examples: 600000
   - name: validation
-    num_bytes: 2805711609
-    num_examples: 600000
+    num_bytes: 960356598
+    num_examples: 150000
   download_size: 1003195420
   dataset_size: 5611423218
 ---
@@ -198,7 +198,7 @@ The data fields are the same among all splits.
 
 |           |train |validation|
 |-----------|-----:|---------:|
-|bypublisher|600000|    600000|
+|bypublisher|600000|    150000|
 
 ## Dataset Creation